INSIGHT Giro St.16: Cold weather does a lot more than cool you off – especially on a 5 hour bike ride over three high mountains. Managing core body heat, energy levels, and actually racing, become a fine and difficult balancing act, as CTS Coach Jim Rutberg explains.

With legendary climbs of the Passo Gavia and Passo Stelvio, and a further summit finish on the Val Martello, Stage 16 of the 2014 Giro d’Italia was going to be a beast in any conditions. But today rain at the lower elevations and snow on the upper slopes of both the Gavia and Stelvio made conditions miserable and led to both confusion and opportunities.

Climbing the Gavia out of the gate kept riders warm – just look at those bare arms.

The climbing began right out of the gate, which in cold and wet weather can be either a blessing or a curse. On the one hand, riders don’t have a lot of time to warm up before having to produce high power outputs, but on the other hand it’s a bit easier to keep your core temperature up in the rain when you’re climbing rather than speeding along flat roads.

For the most part, the front of the peloton stayed huddled together on the Gavia, with riders who were struggling to adapt to the cold temperatures slipping out the back to form chase groups and an eventual grupetto. Keeping warm and fueled was the primary goal for many, and that changes the dynamics of a race.

The number of tasks riders have to complete on the bike impacts their ability to focus. Instead of just thinking about your effort level, your role for the team, and how the stage is unfolding; in poor weather you also have to devote focus to managing core temperature with layers of clothing that come on and off, consuming more fuel than normal to keep your energy levels up, and staying upright on slick roads. It’s more stressful and more mentally exhausting, if not more physically exhausting.

But bad weather can also be an opportunist’s dream. If you’re confident in your handling abilities and you’re feeling aggressive, you can take advantage of the fact that some riders don’t perform as well in cold temperatures, some riders are more conservative descending in wet conditions, and some riders just want to bundle up and survive the cold weather.

The Stelvio climb is 20km long, and at 2760 meters was the coldest point on the day.

Team Movistar’s Nairo Quintana has already shown himself to be a fighter in this year’s Giro d’Italia, and Stage 16 was tailor-made for his strengths. A diminutive figure on the bike, the Colombian is a great climber with the acceleration that comes from having big power and low weight. With time to make up on race leader Rigoberto Uran, Quintana knew today was a day to make the most of any and all opportunities.

There was some confusion at the summit of the Stelvio about whether the descent was going to be neutralized, but the riders appeared to take the approach of “when in doubt, keep going.” Some stopped at the summit to put on extra clothes, which in the long run is a smart move in those conditions. If you’re under-dressed on a long, cold, and wet descent there is very little you can do to retain body heat, and in response to falling core temperature your body will constrict blood flow to the extremities in order to keep your torso and head warm. Your hands get cold and it’s more difficult to operate the brakes and shifters, and by the time you get down to the valley your legs feel like wooden blocks. A large part of riding powerfully in cold weather comes down to maintaining core temperature so your body doesn’t need to constrict blood flow to the extremities.

From the standpoint of core temperature, it may have been better for the riders that the descent off the Stelvio wasn’t neutralized. The plan would have been for the peloton to be led down the descent behind race vehicles, but that would have meant a stoppage for some riders at the cold summit, where they would have lost body heat, followed by a descent where everyone would have been essentially coasting and braking. Going faster on the descent means more wind chill, but you get off the mountain and out of the cold conditions more quickly. You’re also able to pedal more and accelerate out of turns along the way, and that helps you generate heat. With windproof and waterproof clothing I’d much rather get off the top of the mountain as soon as possible and get back down to warmer temperatures and terrain where I can again start using physical exertion to get core temperature up to where it needs to be.

Sammy Sanchez wastes no time getting warm clothes at the finish.

If you only watched the final climb of Stage 16, you might think the whole day was sunny and relatively warm. By 1/3 of the way up the 20-kilometers climb most riders were back to short sleeves. But the two cold climbs and descents had taken their toll. Though the climb featured severe ramps with 14% grades, there were only a few accelerations from either the front group – containing Quintana, Pierre Rolland, and Ryder Hesjedal – or the pink jersey group containing Uran and the rest of the favorites. Though the stage was short on distance – only 139 kilometers – and followed the Giro’s third rest day, no one had the energy left for explosive moves on the Van Martello. Quintana showed his tenacity and great power-to-weight ratio by increasing his lead over the pink jersey group all the way to the line, but even he was too tired at the finish to celebrate winning his first Giro stage and taking the pink leader’s jersey.

Jim Rutberg is a Pro Coach for CTS and co-author of seven books on training and sports nutrition, including “The Time-Crunched Cyclist”. During the Giro d’Italia he will be providing commentary and analysis of key stages, with an eye toward explaining why or how the action happened and what it means for future stages. For information on personal coaching and training camps from CTS, visit http://trainright.com.